The following information was an update made by the CDC on January 6, 2022: The CDC has updated guidance for K-12 schools to align with the updated quarantine and isolation guidance.

Quarantine is a strategy used to prevent transmission of COVID-19 by keeping people who have been in close contact with someone with COVID-19 apart from others. Isolation is used to separate people with confirmed or suspected COVID-19 from those without COVID-19.

Students, teachers, and staff who come into close contact with someone with COVID-19 should quarantine for at least 5 days after their last close contact with someone with COVID-19 if they are in one of the following groups:

• Ages 18 years or older and completed the primary series of recommended vaccine more than 6 months ago but have not received a recommended booster shot.
• Those who have received the single-dose Johnson & Johnson vaccine (completing the primary series) over 2 months ago and have not received a recommended booster shot.
• Those who are not fully vaccinated or have not completed a primary vaccine series.

CDC continues to recommend universal indoor masking by all students (ages 2 years and older), staff, teachers, and visitors to K-12 schools, regardless of vaccination status.

• All students, teachers, and staff who have been exposed to someone with COVID-19 should wear a well-fitting masks around others for 10 days from the date of the last close contact with someone with COVID-19 and watch for symptoms of COVID-19. They should also get tested at least 5 days after having close contact with someone with COVID-19.
• If they test positive or develop COVID-19 symptoms, they should follow recommendations for isolation.
• Students, teachers, and staff who have presumed or confirmed COVID-19 or are showing symptoms of COVID-19 should stay home and isolate away from other people for at least 5 full days.
• People with COVID-19 who have symptoms can end isolation after 5 full days only if they are fever-free for 24 hours without the use of fever-reducing medication and if other symptoms have improved.
• Students, teachers, and staff with COVID-19 should wear a well-fitting mask when around others at home and in public for an additional 5 days after the end of their isolation.

More information can be found at the following links: 

https://www.cdc.gov/coronavirus/2019-ncov/community/schools-childcare/k-12-guidance.html
https://www.cdc.gov/coronavirus/2019-ncov/your-health/quarantine-isolation.html